A Comprehensive Guide to the Tiered Prevention of Coronary Artery Disease: From Primary Risk Intervention to Secondary Drug Treatment Strategies

We hope that coronary heart disease can be effectively controlled in our hands, thereby completely eradicating the basis for sudden cardiac death and freeing all hardworking people from worries.

III. Primary Prevention of Coronary Artery Disease (CAD) Primary prevention of CAD involves intervention of risk factors. Recognized risk factors for CAD include male sex, a family history of early-onset CAD, smoking, hypertension, high-density lipoprotein cholesterol (HDL-C) levels consistently below 0.9 mmol/L (35 mg/dL), diabetes, a history of cerebral or peripheral vascular occlusion, and severe obesity (overweight ≥30%). Except for sex and family history, other risk factors are treatable or preventable.

(I) Lowering Blood Pressure: High blood pressure, high cholesterol, and smoking are considered the three main risk factors for coronary heart disease. Currently, it is emphasized that other risk factors should be controlled simultaneously during antihypertensive treatment, because high blood pressure is often accompanied by high blood lipids, high blood sugar, elevated fibrinogen, and abnormal electrocardiograms.

(II) Lowering serum cholesterol: Experiments show that only by maintaining ideal cholesterol levels for a relatively long period can the prevention of coronary heart disease (CHD) or the prevention of its aggravation be achieved. It is recommended to primarily prevent hyperlipidemia in the population through non-pharmacological methods. First, widespread health education should be conducted. Serum total cholesterol levels are significantly correlated with CHD. When total cholesterol is between 5.2 and 6.21 mmol/L (200–239 mg/dL) or (and LDL-C is between 3.4 and 4.1 mmol/L (130–159 mg/dL), non-pharmacological intervention can be adopted. Individuals with hypercholesterolemia (total cholesterol ≥ 6.24 mmol/L (240 mg/dL)) should adopt both pharmacological and non-pharmacological lipid-lowering measures under the guidance of a doctor.

(III) Promoting smoking cessation and discouraging smoking: Various measures should be taken to move towards a smoke-free society, such as prohibiting teenagers from smoking, advocating that middle-aged people quit smoking, and advising the elderly to smoke less or smoke low-toxicity cigarettes.

(IV) Weight loss primarily involves reducing calorie intake and increasing physical activity. Overweight and obese individuals should reduce their calorie intake. However, methods such as extremely low calorie intake or complete starvation to achieve rapid weight loss are not advisable. Furthermore, because coronary atherosclerosis begins in childhood and adolescence, prevention of coronary heart disease should begin in childhood. Emphasis should be placed on preventing children from becoming overweight, preventing high blood pressure, and preventing children from becoming smokers. Quitting smoking and reducing the intake of high-fat foods can lower the incidence of heart disease. A UN survey in 21 countries showed that reducing smoking and eating less high-fat foods has been effective in lowering the incidence of heart disease. A research report published in the British medical journal *The Lancet* cited several reasons for the decline in heart failure and coronary heart disease mortality rates in developed countries. This project was initiated by the World Health Organization. The goal was to compare the incidence and mortality rates of heart disease between the mid-1980s and mid-1990s, with men and women aged 35 to 64 as the research subjects. The conclusions of the first part of the project were published last May. It showed a significant decline in the incidence of heart disease in developed countries, especially in Northern Europe, the United States, and Australia. In contrast, the incidence rates rose in China, the former Yugoslavia, and parts of Russia. The second part of the report points to the reasons for the decline in incidence: in countries where the incidence rate decreased, men smoked less, and women experienced lower blood pressure. Although some weight was gained during this period, blood cholesterol levels dropped by half due to a more conscious diet. However, the primary reason is that heart disease patients in Western Europe received better treatment. In addition to thrombolytic drugs, they adopted methods such as quitting smoking and controlling their intake of high-fat foods.

IV. Secondary Prevention of Coronary Artery Disease Secondary prevention of coronary artery disease includes health education for patients and their families, targeted measures for risk factors of atherosclerosis, prevention of coronary artery disease progression, drug or surgical treatment of myocardial ischemia, left ventricular dysfunction or severe arrhythmia, and minimizing risk factors for those at high risk of re-infarction or sudden death. (1) By doing a good job in health education, patients and their families can gain an understanding of coronary artery disease and actively cooperate in the prevention and treatment of the disease. (2) Prevent the further development of coronary atherosclerosis or promote its regression. ① Arrange a reasonable diet. A reasonable diet should reduce the intake of total fat, saturated fatty acids and cholesterol. Overweight individuals should limit total calories. If blood lipid levels are significantly abnormal, lipid regulators can be used. ② Encourage smokers to quit smoking. Smoking may induce coronary artery spasm, platelet aggregation, and reduce the reserve capacity of coronary arteries and collateral circulation, which can aggravate coronary artery disease and induce re-infarction. ③ Participate in physical activities and exercise. ④ Comorbid hypertension or diabetes should be properly controlled. (3) Antiplatelet therapy. Platelets play an important role in the formation of atherosclerosis, as well as in myocardial ischemia, myocardial infarction or sudden death caused by coronary artery spasm and thrombosis. Aspirin is an inexpensive and readily available antiplatelet agent with low side effects and is easy to use for a long time. It is especially effective in preventing re-infarction in men. (4) β-adrenergic blockers are currently considered to be effective drugs for secondary prevention after myocardial infarction. They can reduce heart rate and myocardial oxygen consumption, prevent myocardial ischemia and sudden death. (5) Calcium channel blockers have a significant effect on the treatment of angina pectoris, but their effect is poor in the secondary prevention of myocardial infarction. (6) Antiarrhythmic drugs, β-receptor blockers and amiodarone have shown initial efficacy in preventing sudden death, but the focus of sudden death prevention has shifted from delaying conduction to drugs with anti-sympathetic nerve excitation, anti-fibrillation effects and prolonging myocardial refractory period. (7) Treatment of angina pectoris after myocardial infarction should involve a combination of the aforementioned medications in the immediate post-infarction period. Once the condition stabilizes, coronary angiography should be performed, and coronary artery bypass grafting or endovascular angioplasty should be chosen based on the specific lesion. (8) Patients with myocardial infarction complicated by heart failure have a poor prognosis and should undergo further examination to determine the cause of heart failure in order to consider appropriate treatment strategies. Secondary prevention after myocardial infarction can not only prolong the patient's lifespan but also improve their quality of life and ability to return to work. Therefore, secondary prevention should be actively promoted to every patient to effectively reduce the mortality rate of coronary heart disease.